There was confusion, "given the characteristics of the vehicle in which they [the agents] were travelling rubina escort hove they [the suspects] thought they were working for a rival gang," army spokesman Col Ricardo Trevilla said.
Mexican officials presented six lis to the media during a news conference on Wednesday, accusing them of involvement in the attack on the US agents. More on this story.
About sharing image captionJulian Zapata admitted working for the Zetas drug gang, officials said Mexican troops have arrested an alleged drug gang hitman suspected of killing a US immigration agent last week. Drug gangs are also increasingly involved in abducting migrants, often to extort money from their families.
President Calderon said ties were strained after Wikileaks released diplomatic cables, in which US officials criticised Mexico's anti-narcotics efforts. Strains The White House said President Allen md hot wife personals had spoken with President Calderon to thank him for the efforts to bring the attackers to justice.
Three women, among them Mr Zaptata's wife, andwere also detained.
More than 34, people have been killed in drug-related violence in Mexico since Decemberwhen President Calderon's government top notch escorts soldiers and federal police in a widespread crackdown on the illegal cartels. He said Mr Zapata had admitted being the head of a cell working for the Zetas drug gang.
Julian Zapata Espinoza told soldiers he and other gunmen opened fire on the agent's car, thinking it belonged to a rival gang, officials said. It has also emerged that Mr Zapata had been arrested in December but had jumped bail.
Sscorts Zetas and a rival gang, the Gulf Cartel, are vying for control of the San Luis Potosi area, which is also on the route used by illegal migrants seeking to reach the US.